mono/metadata/threadpool.c

   1 /*
   2  * threadpool.c: Microsoft threadpool runtime support
   3  *
   4  * Author:
   5  *      Ludovic Henry (ludovic.henry@xamarin.com)
   6  *
   7  * Copyright 2015 Xamarin, Inc (http://www.xamarin.com)
   8  * Licensed under the MIT license. See LICENSE file in the project root for full license information.
   9  */
  10
  11 //
  12 // Copyright (c) Microsoft. All rights reserved.
  13 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
  14 //
  15 // Files:
  16 //  - src/vm/comthreadpool.cpp
  17 //  - src/vm/win32threadpoolcpp
  18 //  - src/vm/threadpoolrequest.cpp
  19 //  - src/vm/hillclimbing.cpp
  20 //
  21 // Ported from C++ to C and adjusted to Mono runtime
  22
  23 #include <stdlib.h>
  24 #define _USE_MATH_DEFINES // needed by MSVC to define math constants
  25 #include <math.h>
  26 #include <config.h>
  27 #include <glib.h>
  28
  29 #include <mono/metadata/class-internals.h>
  30 #include <mono/metadata/exception.h>
  31 #include <mono/metadata/gc-internals.h>
  32 #include <mono/metadata/object.h>
  33 #include <mono/metadata/object-internals.h>
  34 #include <mono/metadata/threadpool.h>
  35 #include <mono/metadata/threadpool-worker.h>
  36 #include <mono/metadata/threadpool-io.h>
  37 #include <mono/metadata/w32event.h>
  38 #include <mono/utils/atomic.h>
  39 #include <mono/utils/mono-compiler.h>
  40 #include <mono/utils/mono-complex.h>
  41 #include <mono/utils/mono-lazy-init.h>
  42 #include <mono/utils/mono-logger.h>
  43 #include <mono/utils/mono-logger-internals.h>
  44 #include <mono/utils/mono-proclib.h>
  45 #include <mono/utils/mono-threads.h>
  46 #include <mono/utils/mono-time.h>
  47 #include <mono/utils/refcount.h>
  48
  49 typedef struct {
  50         MonoDomain *domain;
  51         /* Number of outstanding jobs */
  52         gint32 outstanding_request;
  53         /* Number of currently executing jobs */
  54         gint32 threadpool_jobs;
  55         /* Signalled when threadpool_jobs + outstanding_request is 0 */
  56         /* Protected by threadpool->domains_lock */
  57         MonoCoopCond cleanup_cond;
  58 } ThreadPoolDomain;
  59
  60 typedef union {
  61         struct {
  62                 gint16 starting; /* starting, but not yet in worker_callback */
  63                 gint16 working; /* executing worker_callback */
  64         } _;
  65         gint32 as_gint32;
  66 } ThreadPoolCounter;
  67
  68 typedef struct {
  69         MonoRefCount ref;
  70
  71         GPtrArray *domains; // ThreadPoolDomain* []
  72         MonoCoopMutex domains_lock;
  73
  74         GPtrArray *threads; // MonoInternalThread* []
  75         MonoCoopMutex threads_lock;
  76         MonoCoopCond threads_exit_cond;
  77
  78         ThreadPoolCounter counters;
  79
  80         gint32 limit_io_min;
  81         gint32 limit_io_max;
  82
  83         MonoThreadPoolWorker *worker;
  84 } ThreadPool;
  85
  86 static mono_lazy_init_t status = MONO_LAZY_INIT_STATUS_NOT_INITIALIZED;
  87
  88 static ThreadPool* threadpool;
  89
  90 #define COUNTER_ATOMIC(threadpool,var,block) \
  91         do { \
  92                 ThreadPoolCounter __old; \
  93                 do { \
  94                         g_assert (threadpool); \
  95                         (var) = __old = COUNTER_READ (threadpool); \
  96                         { block; } \
  97                         if (!(counter._.starting >= 0)) \
  98                                 g_error ("%s: counter._.starting = %d, but should be >= 0", __func__, counter._.starting); \
  99                         if (!(counter._.working >= 0)) \
 100                                 g_error ("%s: counter._.working = %d, but should be >= 0", __func__, counter._.working); \
 101                 } while (InterlockedCompareExchange (&threadpool->counters.as_gint32, (var).as_gint32, __old.as_gint32) != __old.as_gint32); \
 102         } while (0)
 103
 104 static inline ThreadPoolCounter
 105 COUNTER_READ (ThreadPool *threadpool)
 106 {
 107         ThreadPoolCounter counter;
 108         counter.as_gint32 = InterlockedRead (&threadpool->counters.as_gint32);
 109         return counter;
 110 }
 111
 112 static inline void
 113 domains_lock (void)
 114 {
 115         mono_coop_mutex_lock (&threadpool->domains_lock);
 116 }
 117
 118 static inline void
 119 domains_unlock (void)
 120 {
 121         mono_coop_mutex_unlock (&threadpool->domains_lock);
 122 }
 123
 124 static void
 125 destroy (gpointer unused)
 126 {
 127         g_ptr_array_free (threadpool->domains, TRUE);
 128         mono_coop_mutex_destroy (&threadpool->domains_lock);
 129
 130         g_ptr_array_free (threadpool->threads, TRUE);
 131         mono_coop_mutex_destroy (&threadpool->threads_lock);
 132         mono_coop_cond_destroy (&threadpool->threads_exit_cond);
 133
 134         g_free (threadpool);
 135 }
 136
 137 static void
 138 initialize (void)
 139 {
 140         g_assert (!threadpool);
 141         threadpool = g_new0 (ThreadPool, 1);
 142         g_assert (threadpool);
 143
 144         g_assert (sizeof (ThreadPoolCounter) == sizeof (gint32));
 145
 146         mono_refcount_init (threadpool, destroy);
 147
 148         threadpool->domains = g_ptr_array_new ();
 149         mono_coop_mutex_init (&threadpool->domains_lock);
 150
 151         threadpool->threads = g_ptr_array_new ();
 152         mono_coop_mutex_init (&threadpool->threads_lock);
 153         mono_coop_cond_init (&threadpool->threads_exit_cond);
 154
 155         threadpool->limit_io_min = mono_cpu_count ();
 156         threadpool->limit_io_max = CLAMP (threadpool->limit_io_min * 100, MIN (threadpool->limit_io_min, 200), MAX (threadpool->limit_io_min, 200));
 157
 158         mono_threadpool_worker_init (&threadpool->worker);
 159 }
 160
 161 static void
 162 cleanup (void)
 163 {
 164         guint i;
 165         MonoInternalThread *current;
 166
 167         /* we make the assumption along the code that we are
 168          * cleaning up only if the runtime is shutting down */
 169         g_assert (mono_runtime_is_shutting_down ());
 170
 171         current = mono_thread_internal_current ();
 172
 173         mono_coop_mutex_lock (&threadpool->threads_lock);
 174
 175         /* stop all threadpool->threads */
 176         for (i = 0; i < threadpool->threads->len; ++i) {
 177                 MonoInternalThread *thread = (MonoInternalThread*) g_ptr_array_index (threadpool->threads, i);
 178                 if (thread != current)
 179                         mono_thread_internal_abort (thread);
 180         }
 181
 182         mono_coop_mutex_unlock (&threadpool->threads_lock);
 183
 184         /* give a chance to the other threads to exit */
 185         mono_thread_info_yield ();
 186
 187         mono_coop_mutex_lock (&threadpool->threads_lock);
 188
 189         for (;;) {
 190                 if (threadpool->threads->len == 0)
 191                         break;
 192
 193                 if (threadpool->threads->len == 1 && g_ptr_array_index (threadpool->threads, 0) == current) {
 194                         /* We are waiting on ourselves */
 195                         break;
 196                 }
 197
 198                 mono_coop_cond_wait (&threadpool->threads_exit_cond, &threadpool->threads_lock);
 199         }
 200
 201         mono_coop_mutex_unlock (&threadpool->threads_lock);
 202
 203         mono_threadpool_worker_cleanup (threadpool->worker);
 204
 205         mono_refcount_dec (threadpool);
 206 }
 207
 208 gboolean
 209 mono_threadpool_enqueue_work_item (MonoDomain *domain, MonoObject *work_item, MonoError *error)
 210 {
 211         static MonoClass *threadpool_class = NULL;
 212         static MonoMethod *unsafe_queue_custom_work_item_method = NULL;
 213         MonoDomain *current_domain;
 214         MonoBoolean f;
 215         gpointer args [2];
 216
 217         mono_error_init (error);
 218         g_assert (work_item);
 219
 220         if (!threadpool_class)
 221                 threadpool_class = mono_class_load_from_name (mono_defaults.corlib, "System.Threading", "ThreadPool");
 222
 223         if (!unsafe_queue_custom_work_item_method)
 224                 unsafe_queue_custom_work_item_method = mono_class_get_method_from_name (threadpool_class, "UnsafeQueueCustomWorkItem", 2);
 225         g_assert (unsafe_queue_custom_work_item_method);
 226
 227         f = FALSE;
 228
 229         args [0] = (gpointer) work_item;
 230         args [1] = (gpointer) &f;
 231
 232         current_domain = mono_domain_get ();
 233         if (current_domain == domain) {
 234                 mono_runtime_invoke_checked (unsafe_queue_custom_work_item_method, NULL, args, error);
 235                 return_val_if_nok (error, FALSE);
 236         } else {
 237                 mono_thread_push_appdomain_ref (domain);
 238                 if (mono_domain_set (domain, FALSE)) {
 239                         mono_runtime_invoke_checked (unsafe_queue_custom_work_item_method, NULL, args, error);
 240                         if (!is_ok (error)) {
 241                                 mono_thread_pop_appdomain_ref ();
 242                                 return FALSE;
 243                         }
 244                         mono_domain_set (current_domain, TRUE);
 245                 }
 246                 mono_thread_pop_appdomain_ref ();
 247         }
 248         return TRUE;
 249 }
 250
 251 /* LOCKING: domains_lock must be held */
 252 static void
 253 tpdomain_add (ThreadPoolDomain *tpdomain)
 254 {
 255         guint i, len;
 256
 257         g_assert (tpdomain);
 258
 259         len = threadpool->domains->len;
 260         for (i = 0; i < len; ++i) {
 261                 if (g_ptr_array_index (threadpool->domains, i) == tpdomain)
 262                         break;
 263         }
 264
 265         if (i == len)
 266                 g_ptr_array_add (threadpool->domains, tpdomain);
 267 }
 268
 269 /* LOCKING: domains_lock must be held. */
 270 static gboolean
 271 tpdomain_remove (ThreadPoolDomain *tpdomain)
 272 {
 273         g_assert (tpdomain);
 274         return g_ptr_array_remove (threadpool->domains, tpdomain);
 275 }
 276
 277 /* LOCKING: domains_lock must be held */
 278 static ThreadPoolDomain *
 279 tpdomain_get (MonoDomain *domain, gboolean create)
 280 {
 281         guint i;
 282         ThreadPoolDomain *tpdomain;
 283
 284         g_assert (domain);
 285
 286         for (i = 0; i < threadpool->domains->len; ++i) {
 287                 ThreadPoolDomain *tpdomain;
 288
 289                 tpdomain = (ThreadPoolDomain *)g_ptr_array_index (threadpool->domains, i);
 290                 if (tpdomain->domain == domain)
 291                         return tpdomain;
 292         }
 293
 294         if (!create)
 295                 return NULL;
 296
 297         tpdomain = g_new0 (ThreadPoolDomain, 1);
 298         tpdomain->domain = domain;
 299         mono_coop_cond_init (&tpdomain->cleanup_cond);
 300
 301         tpdomain_add (tpdomain);
 302
 303         return tpdomain;
 304 }
 305
 306 static void
 307 tpdomain_free (ThreadPoolDomain *tpdomain)
 308 {
 309         g_free (tpdomain);
 310 }
 311
 312 /* LOCKING: domains_lock must be held */
 313 static ThreadPoolDomain *
 314 tpdomain_get_next (ThreadPoolDomain *current)
 315 {
 316         ThreadPoolDomain *tpdomain = NULL;
 317         guint len;
 318
 319         len = threadpool->domains->len;
 320         if (len > 0) {
 321                 guint i, current_idx = -1;
 322                 if (current) {
 323                         for (i = 0; i < len; ++i) {
 324                                 if (current == g_ptr_array_index (threadpool->domains, i)) {
 325                                         current_idx = i;
 326                                         break;
 327                                 }
 328                         }
 329                         g_assert (current_idx != (guint)-1);
 330                 }
 331                 for (i = current_idx + 1; i < len + current_idx + 1; ++i) {
 332                         ThreadPoolDomain *tmp = (ThreadPoolDomain *)g_ptr_array_index (threadpool->domains, i % len);
 333                         if (tmp->outstanding_request > 0) {
 334                                 tpdomain = tmp;
 335                                 break;
 336                         }
 337                 }
 338         }
 339
 340         return tpdomain;
 341 }
 342
 343 static MonoObject*
 344 try_invoke_perform_wait_callback (MonoObject** exc, MonoError *error)
 345 {
 346         HANDLE_FUNCTION_ENTER ();
 347         mono_error_init (error);
 348         MonoObject *res = mono_runtime_try_invoke (mono_defaults.threadpool_perform_wait_callback_method, NULL, NULL, exc, error);
 349         HANDLE_FUNCTION_RETURN_VAL (res);
 350 }
 351
 352 static void
 353 worker_callback (gpointer unused)
 354 {
 355         MonoError error;
 356         ThreadPoolDomain *tpdomain, *previous_tpdomain;
 357         ThreadPoolCounter counter;
 358         MonoInternalThread *thread;
 359
 360         thread = mono_thread_internal_current ();
 361
 362         COUNTER_ATOMIC (threadpool, counter, {
 363                 if (!(counter._.working < 32767 /* G_MAXINT16 */))
 364                         g_error ("%s: counter._.working = %d, but should be < 32767", __func__, counter._.working);
 365
 366                 counter._.starting --;
 367                 counter._.working ++;
 368         });
 369
 370         if (mono_runtime_is_shutting_down ()) {
 371                 COUNTER_ATOMIC (threadpool, counter, {
 372                         counter._.working --;
 373                 });
 374
 375                 mono_refcount_dec (threadpool);
 376                 return;
 377         }
 378
 379         mono_coop_mutex_lock (&threadpool->threads_lock);
 380         g_ptr_array_add (threadpool->threads, thread);
 381         mono_coop_mutex_unlock (&threadpool->threads_lock);
 382
 383         /*
 384          * This is needed so there is always an lmf frame in the runtime invoke call below,
 385          * so ThreadAbortExceptions are caught even if the thread is in native code.
 386          */
 387         mono_defaults.threadpool_perform_wait_callback_method->save_lmf = TRUE;
 388
 389         domains_lock ();
 390
 391         previous_tpdomain = NULL;
 392
 393         while (!mono_runtime_is_shutting_down ()) {
 394                 gboolean retire = FALSE;
 395
 396                 if ((thread->state & (ThreadState_AbortRequested | ThreadState_SuspendRequested)) != 0) {
 397                         domains_unlock ();
 398                         mono_thread_interruption_checkpoint ();
 399                         domains_lock ();
 400                 }
 401
 402                 tpdomain = tpdomain_get_next (previous_tpdomain);
 403                 if (!tpdomain)
 404                         break;
 405
 406                 tpdomain->outstanding_request --;
 407                 g_assert (tpdomain->outstanding_request >= 0);
 408
 409                 mono_trace (G_LOG_LEVEL_DEBUG, MONO_TRACE_THREADPOOL, "[%p] worker running in domain %p (outstanding requests %d)",
 410                         mono_native_thread_id_get (), tpdomain->domain, tpdomain->outstanding_request);
 411
 412                 g_assert (tpdomain->threadpool_jobs >= 0);
 413                 tpdomain->threadpool_jobs ++;
 414
 415                 domains_unlock ();
 416
 417                 mono_thread_clr_state (thread, (MonoThreadState)~ThreadState_Background);
 418                 if (!mono_thread_test_state (thread , ThreadState_Background))
 419                         ves_icall_System_Threading_Thread_SetState (thread, ThreadState_Background);
 420
 421                 mono_thread_push_appdomain_ref (tpdomain->domain);
 422                 if (mono_domain_set (tpdomain->domain, FALSE)) {
 423                         MonoObject *exc = NULL, *res;
 424
 425                         res = try_invoke_perform_wait_callback (&exc, &error);
 426                         if (exc || !mono_error_ok(&error)) {
 427                                 if (exc == NULL)
 428                                         exc = (MonoObject *) mono_error_convert_to_exception (&error);
 429                                 else
 430                                         mono_error_cleanup (&error);
 431                                 mono_thread_internal_unhandled_exception (exc);
 432                         } else if (res && *(MonoBoolean*) mono_object_unbox (res) == FALSE) {
 433                                 retire = TRUE;
 434                         }
 435
 436                         mono_domain_set (mono_get_root_domain (), TRUE);
 437                 }
 438                 mono_thread_pop_appdomain_ref ();
 439
 440                 domains_lock ();
 441
 442                 tpdomain->threadpool_jobs --;
 443                 g_assert (tpdomain->threadpool_jobs >= 0);
 444
 445                 if (tpdomain->outstanding_request + tpdomain->threadpool_jobs == 0 && mono_domain_is_unloading (tpdomain->domain)) {
 446                         gboolean removed;
 447
 448                         removed = tpdomain_remove (tpdomain);
 449                         g_assert (removed);
 450
 451                         mono_coop_cond_signal (&tpdomain->cleanup_cond);
 452                         tpdomain = NULL;
 453                 }
 454
 455                 if (retire)
 456                         break;
 457
 458                 previous_tpdomain = tpdomain;
 459         }
 460
 461         domains_unlock ();
 462
 463         mono_coop_mutex_lock (&threadpool->threads_lock);
 464
 465         g_ptr_array_remove_fast (threadpool->threads, thread);
 466
 467         mono_coop_cond_signal (&threadpool->threads_exit_cond);
 468
 469         mono_coop_mutex_unlock (&threadpool->threads_lock);
 470
 471         COUNTER_ATOMIC (threadpool, counter, {
 472                 counter._.working --;
 473         });
 474
 475         mono_refcount_dec (threadpool);
 476 }
 477
 478 void
 479 mono_threadpool_cleanup (void)
 480 {
 481 #ifndef DISABLE_SOCKETS
 482         mono_threadpool_io_cleanup ();
 483 #endif
 484         mono_lazy_cleanup (&status, cleanup);
 485 }
 486
 487 MonoAsyncResult *
 488 mono_threadpool_begin_invoke (MonoDomain *domain, MonoObject *target, MonoMethod *method, gpointer *params, MonoError *error)
 489 {
 490         static MonoClass *async_call_klass = NULL;
 491         MonoMethodMessage *message;
 492         MonoAsyncResult *async_result;
 493         MonoAsyncCall *async_call;
 494         MonoDelegate *async_callback = NULL;
 495         MonoObject *state = NULL;
 496
 497         if (!async_call_klass)
 498                 async_call_klass = mono_class_load_from_name (mono_defaults.corlib, "System", "MonoAsyncCall");
 499
 500         mono_lazy_initialize (&status, initialize);
 501
 502         mono_error_init (error);
 503
 504         message = mono_method_call_message_new (method, params, mono_get_delegate_invoke (method->klass), (params != NULL) ? (&async_callback) : NULL, (params != NULL) ? (&state) : NULL, error);
 505         return_val_if_nok (error, NULL);
 506
 507         async_call = (MonoAsyncCall*) mono_object_new_checked (domain, async_call_klass, error);
 508         return_val_if_nok (error, NULL);
 509
 510         MONO_OBJECT_SETREF (async_call, msg, message);
 511         MONO_OBJECT_SETREF (async_call, state, state);
 512
 513         if (async_callback) {
 514                 MONO_OBJECT_SETREF (async_call, cb_method, mono_get_delegate_invoke (((MonoObject*) async_callback)->vtable->klass));
 515                 MONO_OBJECT_SETREF (async_call, cb_target, async_callback);
 516         }
 517
 518         async_result = mono_async_result_new (domain, NULL, async_call->state, NULL, (MonoObject*) async_call, error);
 519         return_val_if_nok (error, NULL);
 520         MONO_OBJECT_SETREF (async_result, async_delegate, target);
 521
 522         mono_threadpool_enqueue_work_item (domain, (MonoObject*) async_result, error);
 523         return_val_if_nok (error, NULL);
 524
 525         return async_result;
 526 }
 527
 528 MonoObject *
 529 mono_threadpool_end_invoke (MonoAsyncResult *ares, MonoArray **out_args, MonoObject **exc, MonoError *error)
 530 {
 531         MonoAsyncCall *ac;
 532
 533         mono_error_init (error);
 534         g_assert (exc);
 535         g_assert (out_args);
 536
 537         *exc = NULL;
 538         *out_args = NULL;
 539
 540         /* check if already finished */
 541         mono_monitor_enter ((MonoObject*) ares);
 542
 543         if (ares->endinvoke_called) {
 544                 mono_error_set_invalid_operation(error, "Delegate EndInvoke method called more than once");
 545                 mono_monitor_exit ((MonoObject*) ares);
 546                 return NULL;
 547         }
 548
 549         ares->endinvoke_called = 1;
 550
 551         /* wait until we are really finished */
 552         if (ares->completed) {
 553                 mono_monitor_exit ((MonoObject *) ares);
 554         } else {
 555                 gpointer wait_event;
 556                 if (ares->handle) {
 557                         wait_event = mono_wait_handle_get_handle ((MonoWaitHandle*) ares->handle);
 558                 } else {
 559                         wait_event = mono_w32event_create (TRUE, FALSE);
 560                         g_assert(wait_event);
 561                         MonoWaitHandle *wait_handle = mono_wait_handle_new (mono_object_domain (ares), wait_event, error);
 562                         if (!is_ok (error)) {
 563                                 CloseHandle (wait_event);
 564                                 return NULL;
 565                         }
 566                         MONO_OBJECT_SETREF (ares, handle, (MonoObject*) wait_handle);
 567                 }
 568                 mono_monitor_exit ((MonoObject*) ares);
 569                 MONO_ENTER_GC_SAFE;
 570 #ifdef HOST_WIN32
 571                 WaitForSingleObjectEx (wait_event, INFINITE, TRUE);
 572 #else
 573                 mono_w32handle_wait_one (wait_event, MONO_INFINITE_WAIT, TRUE);
 574 #endif
 575                 MONO_EXIT_GC_SAFE;
 576         }
 577
 578         ac = (MonoAsyncCall*) ares->object_data;
 579         g_assert (ac);
 580
 581         *exc = ac->msg->exc; /* FIXME: GC add write barrier */
 582         *out_args = ac->out_args;
 583         return ac->res;
 584 }
 585
 586 gboolean
 587 mono_threadpool_remove_domain_jobs (MonoDomain *domain, int timeout)
 588 {
 589         gint64 end;
 590         ThreadPoolDomain *tpdomain;
 591         gboolean ret;
 592
 593         g_assert (domain);
 594         g_assert (timeout >= -1);
 595
 596         g_assert (mono_domain_is_unloading (domain));
 597
 598         if (timeout != -1)
 599                 end = mono_msec_ticks () + timeout;
 600
 601 #ifndef DISABLE_SOCKETS
 602         mono_threadpool_io_remove_domain_jobs (domain);
 603         if (timeout != -1) {
 604                 if (mono_msec_ticks () > end)
 605                         return FALSE;
 606         }
 607 #endif
 608
 609         /*
 610          * Wait for all threads which execute jobs in the domain to exit.
 611          * The is_unloading () check in worker_request () ensures that
 612          * no new jobs are added after we enter the lock below.
 613          */
 614
 615         if (!mono_lazy_is_initialized (&status))
 616                 return TRUE;
 617
 618         mono_refcount_inc (threadpool);
 619
 620         domains_lock ();
 621
 622         tpdomain = tpdomain_get (domain, FALSE);
 623         if (!tpdomain) {
 624                 domains_unlock ();
 625                 mono_refcount_dec (threadpool);
 626                 return TRUE;
 627         }
 628
 629         ret = TRUE;
 630
 631         while (tpdomain->outstanding_request + tpdomain->threadpool_jobs > 0) {
 632                 if (timeout == -1) {
 633                         mono_coop_cond_wait (&tpdomain->cleanup_cond, &threadpool->domains_lock);
 634                 } else {
 635                         gint64 now;
 636                         gint res;
 637
 638                         now = mono_msec_ticks();
 639                         if (now > end) {
 640                                 ret = FALSE;
 641                                 break;
 642                         }
 643
 644                         res = mono_coop_cond_timedwait (&tpdomain->cleanup_cond, &threadpool->domains_lock, end - now);
 645                         if (res != 0) {
 646                                 ret = FALSE;
 647                                 break;
 648                         }
 649                 }
 650         }
 651
 652         /* Remove from the list the worker threads look at */
 653         tpdomain_remove (tpdomain);
 654
 655         domains_unlock ();
 656
 657         mono_coop_cond_destroy (&tpdomain->cleanup_cond);
 658         tpdomain_free (tpdomain);
 659
 660         mono_refcount_dec (threadpool);
 661
 662         return ret;
 663 }
 664
 665 void
 666 mono_threadpool_suspend (void)
 667 {
 668         if (threadpool)
 669                 mono_threadpool_worker_set_suspended (threadpool->worker, TRUE);
 670 }
 671
 672 void
 673 mono_threadpool_resume (void)
 674 {
 675         if (threadpool)
 676                 mono_threadpool_worker_set_suspended (threadpool->worker, FALSE);
 677 }
 678
 679 void
 680 ves_icall_System_Threading_ThreadPool_GetAvailableThreadsNative (gint32 *worker_threads, gint32 *completion_port_threads)
 681 {
 682         ThreadPoolCounter counter;
 683
 684         if (!worker_threads || !completion_port_threads)
 685                 return;
 686
 687         mono_lazy_initialize (&status, initialize);
 688
 689         counter = COUNTER_READ (threadpool);
 690
 691         *worker_threads = MAX (0, mono_threadpool_worker_get_max (threadpool->worker) - counter._.working);
 692         *completion_port_threads = threadpool->limit_io_max;
 693 }
 694
 695 void
 696 ves_icall_System_Threading_ThreadPool_GetMinThreadsNative (gint32 *worker_threads, gint32 *completion_port_threads)
 697 {
 698         if (!worker_threads || !completion_port_threads)
 699                 return;
 700
 701         mono_lazy_initialize (&status, initialize);
 702
 703         *worker_threads = mono_threadpool_worker_get_min (threadpool->worker);
 704         *completion_port_threads = threadpool->limit_io_min;
 705 }
 706
 707 void
 708 ves_icall_System_Threading_ThreadPool_GetMaxThreadsNative (gint32 *worker_threads, gint32 *completion_port_threads)
 709 {
 710         if (!worker_threads || !completion_port_threads)
 711                 return;
 712
 713         mono_lazy_initialize (&status, initialize);
 714
 715         *worker_threads = mono_threadpool_worker_get_max (threadpool->worker);
 716         *completion_port_threads = threadpool->limit_io_max;
 717 }
 718
 719 MonoBoolean
 720 ves_icall_System_Threading_ThreadPool_SetMinThreadsNative (gint32 worker_threads, gint32 completion_port_threads)
 721 {
 722         mono_lazy_initialize (&status, initialize);
 723
 724         if (completion_port_threads <= 0 || completion_port_threads > threadpool->limit_io_max)
 725                 return FALSE;
 726
 727         if (!mono_threadpool_worker_set_min (threadpool->worker, worker_threads))
 728                 return FALSE;
 729
 730         threadpool->limit_io_min = completion_port_threads;
 731
 732         return TRUE;
 733 }
 734
 735 MonoBoolean
 736 ves_icall_System_Threading_ThreadPool_SetMaxThreadsNative (gint32 worker_threads, gint32 completion_port_threads)
 737 {
 738         gint cpu_count = mono_cpu_count ();
 739
 740         mono_lazy_initialize (&status, initialize);
 741
 742         if (completion_port_threads < threadpool->limit_io_min || completion_port_threads < cpu_count)
 743                 return FALSE;
 744
 745         if (!mono_threadpool_worker_set_max (threadpool->worker, worker_threads))
 746                 return FALSE;
 747
 748         threadpool->limit_io_max = completion_port_threads;
 749
 750         return TRUE;
 751 }
 752
 753 void
 754 ves_icall_System_Threading_ThreadPool_InitializeVMTp (MonoBoolean *enable_worker_tracking)
 755 {
 756         if (enable_worker_tracking) {
 757                 // TODO implement some kind of switch to have the possibily to use it
 758                 *enable_worker_tracking = FALSE;
 759         }
 760
 761         mono_lazy_initialize (&status, initialize);
 762 }
 763
 764 MonoBoolean
 765 ves_icall_System_Threading_ThreadPool_NotifyWorkItemComplete (void)
 766 {
 767         if (mono_domain_is_unloading (mono_domain_get ()) || mono_runtime_is_shutting_down ())
 768                 return FALSE;
 769
 770         return mono_threadpool_worker_notify_completed (threadpool->worker);
 771 }
 772
 773 void
 774 ves_icall_System_Threading_ThreadPool_NotifyWorkItemProgressNative (void)
 775 {
 776         mono_threadpool_worker_notify_completed (threadpool->worker);
 777 }
 778
 779 void
 780 ves_icall_System_Threading_ThreadPool_ReportThreadStatus (MonoBoolean is_working)
 781 {
 782         // TODO
 783         MonoError error;
 784         mono_error_set_not_implemented (&error, "");
 785         mono_error_set_pending_exception (&error);
 786 }
 787
 788 MonoBoolean
 789 ves_icall_System_Threading_ThreadPool_RequestWorkerThread (void)
 790 {
 791         MonoDomain *domain;
 792         ThreadPoolDomain *tpdomain;
 793         ThreadPoolCounter counter;
 794
 795         domain = mono_domain_get ();
 796         if (mono_domain_is_unloading (domain))
 797                 return FALSE;
 798
 799         domains_lock ();
 800
 801         /* synchronize with mono_threadpool_remove_domain_jobs */
 802         if (mono_domain_is_unloading (domain)) {
 803                 domains_unlock ();
 804                 return FALSE;
 805         }
 806
 807         tpdomain = tpdomain_get (domain, TRUE);
 808         g_assert (tpdomain);
 809
 810         tpdomain->outstanding_request ++;
 811         g_assert (tpdomain->outstanding_request >= 1);
 812
 813         domains_unlock ();
 814
 815         COUNTER_ATOMIC (threadpool, counter, {
 816                 if (counter._.starting == 16)
 817                         return TRUE;
 818
 819                 counter._.starting ++;
 820         });
 821
 822         mono_refcount_inc (threadpool);
 823
 824         mono_threadpool_worker_enqueue (threadpool->worker, worker_callback, NULL);
 825
 826         return TRUE;
 827 }
 828
 829 MonoBoolean G_GNUC_UNUSED
 830 ves_icall_System_Threading_ThreadPool_PostQueuedCompletionStatus (MonoNativeOverlapped *native_overlapped)
 831 {
 832         /* This copy the behavior of the current Mono implementation */
 833         MonoError error;
 834         mono_error_set_not_implemented (&error, "");
 835         mono_error_set_pending_exception (&error);
 836         return FALSE;
 837 }
 838
 839 MonoBoolean G_GNUC_UNUSED
 840 ves_icall_System_Threading_ThreadPool_BindIOCompletionCallbackNative (gpointer file_handle)
 841 {
 842         /* This copy the behavior of the current Mono implementation */
 843         return TRUE;
 844 }
 845
 846 MonoBoolean G_GNUC_UNUSED
 847 ves_icall_System_Threading_ThreadPool_IsThreadPoolHosted (void)
 848 {
 849         return FALSE;
 850 }